Ritamulse SCG (INCI: Glyceryl stearate (and) cetearyl alcohol (and) sodium stearoyl lactylate) is an Ecocert self-emulsifier that can be used at 2% to 10% to emulsify up to 25% oils in an oil in the water emulsion, although I've found that almost every sample recipe I've seen uses 8% or higher. It works best at pH 5 to 7.5, which means it isn't a great choice for moisturizers that might contain AHA or other acidic ingredients. It is plant derived, and claims to have a "silky, soft, talc-like feel". As you can see in the picture, it comes in off-white waxy flakes that must be used in the heated oil phase of your lotion. Its melting point is around 50˚C.
When using this ingredient, you want to heat and hold your water and oil phases, then add the water phase to the oil phase in a thin stream. They suggest mixing it until it reaches 30˚C. I have found that I can mix it for a few minutes after combining the two phases, leave it a bit, add my cool down phase, then mix it further and still have a really stable product.
Do not add your cool down phase until you reach 45˚C or lower. I tried adding my cool down at around 49˚C, and I had separation within a few minutes. It turned into a cottage cheese looking product! So gross!
Ritamulse SCG doesn't play well with acidic ingredients, like AHA or lactic acids, and it's not great with cationic ingredients, so you don't want to include any cationic polymers or cationic compounds, like Incroquat CR, cetrimonium chloride, cetrimonium bromide, or Incroquat BTMS-50.
1. I cannot stress enough how you don't want to go over 25% oils. It will result in a serious lotion fail, like the one you see here.
2. Do not add your cool down phase before you reach 45˚C. It will result in a serious lotion fail.
3. Do not use really acidic ingredients like AHAs or lactic acids as you will result in a lotion fail. This isn't the emulsifier for things like fancy moisturizers with loads of AHAs.
4. Do not use cationic ingredients in this product.
How would we alter a recipe like basic lotion we created the other day using Polawax? First, check to make sure the oil phase is less than 25%. Make sure you don't have cationic or really acidic ingredients. Then substitute the amount of Ritamulse SCG for the Polawax amount at the suggested rate. I have found the most stability with 8% Ritamulse SCG in my lotions with 25% oils. (Your mileage may vary...) So I'm going to substitute the 6% Polawax from the basic recipe with 8% Ritamulse SCG. This means that I will have to remove 2% from the water phase to make the recipe balance out.
BASIC LOTION RECIPE
HEATED WATER PHASE (68.5% of the lotion)
HEATED OIL PHASE (29% of the lotion)
8% Ritamulse SCG
COOL DOWN PHASE (1.5% of the lotion)
1% fragrance or essential oil
0.5% preservative (I use liquid Germall Plus)
Another consideration here. Ritamulse SCG contains cetearyl alcohol, which I have found can feel a little waxier than using something like Polawax. I wouldn't suggest using cetearyl alcohol as your thickener as it can get a bit much, but that's a personal choice.
Join me tomorrow as we take a look at using Incroquat BTMS-50 as our emulsifier!